Electron cyclotron resonance heating in a short

cylindrical plasma system

 

VIPIN K YADAV and D BORA

Institute for Plasma Research, Bhat, Gandhinagar 382 428, India

E-mail: vipin@ipr.res.in; dbora@ipr.res.in

 

Abstract.  Electron cyclotron resonance (ECR) plasma is produced and studied in a

small cylindrical system. Microwave power is delivered by a CW

magnetron at 2.45 GHz in TE$_{10}$ mode and launched radially to have

extraordinary (X) wave in plasma. The axial magnetic field required for

ECR in the system is such that the first two ECR surfaces ($B = 875.0$ G

and $B = 437.5$ G) reside in the system. ECR plasma is produced with

hydrogen with typical plasma density $n_{\rm e}$ as $3.2 \times 10^{10}$

cm$^{-3}$ and plasma temperature $T_{\rm e}$ between 9 and 15 eV. Various cut-off

and resonance positions are identified in the plasma system. ECR

heating (ECRH) of the plasma is observed experimentally. This heating

is because of the mode conversion of X-wave to electron Bernstein wave

(EBW) at the upper hybrid resonance (UHR) layer. The power mode

conversion efficiency is estimated to be 0.85 for this system. The

experimental results are presented in this paper.

 

Keywords. X-wave; electron cyclotron resonance; upper hybrid resonance.

 

PACS Nos 52.35.Hr, 52.50.Sw, 52.70.Gw